Resistance is reportedly hardening against presumptive nominee Donald Trump among some Senate Republicans — even as a die-hard, anti-Trump contingent continues to buck long odds in a plot to make a last stand at the party's convention.

"Whoever's our candidate, I'm going to support our candidate," Sen. James Lankford of Oklahoma tells Politico. "I'll feel better when I get a list of policies and I see who the vice president is."

Maine Sen. Susan Collins tells Politico she's "still evaluating," and Nevada Sen. Dean Heller tells the outlet, "Today, I'm opposed to his campaign," adding: "I'll give him a chance, but at this point, I have no intentions of voting for him."

Meanwhile, The Hill reports that anti-Trump delegates, lawyers, rules experts and Political Action Committees are setting up for a last-ditch effort to deny the real estate mogul the party's nomination.

"This is a laser-guided bomb aimed right at the foundation of the Trump campaign," Beau Correll, a Virginia delegate and central figure in the opposition movement, tells The Hill.

No one at the Republican National Convention or within the Trump campaign is worried about the revolt, with Republican National Committee strategist Sean Spicer telling The Hill the uprising is little more than "tweets and media fascination."

"They've laid down the dried leaves to start the fire but they need lightning to strike," one unnamed conservative lawyer tells The Hill. "It is really tough to organize the kind of whip operation you need at something as sprawling as Republican National Convention. Really, really tough."

Still, the effort seems more organized than previous anti-Trump efforts, The Hill reports.

Conservative media figures Erick Erickson, Steve Deace, and Bill Kristol have begun joining the conference calls for the coalition, and there's considerable interest in Correll's lawsuit challenging a Virginia state law that binds delegates to the primary winner.

A win "would be like a shot of Red Bull straight to the vein," Kendal Unruh, a Colorado delegate and one of the main organizers of the planned convention revolt, tells The Hill.

She sits on the Rules Committee and is waging a campaign to achieve 57 votes from the 112-member panel in favor of a "conscience clause" that would unbind delegates to support whomever they choose.

And, according to The Hill, Colorado conservative activist Regina Thomson, who runs a PAC called Free the Delegates, is organizing a floor fight irrespective of any Rules Committee's decision, while Delegates Unbound, led by GOP strategist Dane Waters, is overseeing a national lobbying campaign focused on contacting delegates before they arrive in Cleveland to urge them to vote their conscience.

The unnamed lawyer doesn't see how it can work.

"I don't see anything here that would spark a stampede away from Trump," the lawyer tells The Hill. "What sets off the stampede is Trump doing badly in the polls and Senate candidates falling behind because of it. They need someone, somewhere, like Reince Priebus or [House Speaker] Paul Ryan or [Senate Majority Leader] Mitch McConnell to show an ounce of leadership if they're to be successful. That's been nonexistent so far."

Resistance is reportedly hardening against presumptive nominee Donald Trump among some Senate Republicans - even as a die-hard, anti-Trump contingent continues to buck long odds in a plot to make a last stand at the party's convention.